Switched reluctance motor assembly

ABSTRACT

Disclosed herein is a switched reluctance motor assembly capable of reducing an assembling error that is generated according to separate assembling and improving precision of assembling of bearing parts by forming a diffuser part and a motor housing integrally with each other. In the switched reluctance motor assembly, the diffuser is coupled integrally with the housing, such that a separate member for fixing the diffuser is omitted, thereby making it possible to reduce vibration according to driving of a motor and noise according to the vibration.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2012-0091814, filed on Aug. 22, 2012, entitled “Switched Reluctance Motor Assembly”, which is hereby incorporated by reference in its entirety into this application.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a switched reluctance motor assembly.

2. Description of the Related Art

Generally, a switched reluctance motor (SRM) called an SR motor is a motor in which both of a stator and a rotor have a magnetic structure, which is a salient pole, the stator has a concentrated type coil wound therearound, and the rotor is configured only of an iron core without any type of excitation device (a winding or a permanent magnet), such that a competitive cost is excellent.

More specifically, the switched reluctance motor (SRM), which rotates a rotor using a reluctance torque according to a change in magnetic reluctance, has a low manufacturing cost, hardly requires maintenance, and has an almost permanent lifespan due to high reliability. The switched reluctance motor is configured to include: a stator part, which is a stator, including a stator yoke and a plurality of stator salient poles protruded from the stator yoke; and a rotor part, which is a rotor, including a rotor core and a plurality of rotor salient poles protruded from the rotor core so as to face the stator salient poles and rotatably received in the stator part.

This switched reluctance motor (SRM) has been used in various fields such as a vacuum cleaner, or the like. However, due to vibration or noise generated at the time of driving the switched reluctance motor (SRM) mounted in a vacuum cleaner module, operation performance of a product is deteriorated. In addition, coupling force of two bearing parts coupled to upper and lower portions of a shaft are reduced, such that it is difficult to secure concentricity of the two bearing parts. As a result, vibration and noise are generated due to the bearing parts at the time of an operation of the motor. Therefore, a lifespan of the entire product including the motor is reduced.

SUMMARY OF THE INVENTION

The present invention has been made in an effort to provide a switched reluctance motor assembly that is capable of improving productivity by integrally forming a diffuser and a housing of a vacuum cleaner module including a switched reluctance motor with each other to simplify a product structure and is capable of improving operation performance and reliability of a product by implementing a more stable support structure of a bearing part.

According to a preferred embodiment of the present invention, there is provided a switched reluctance motor assembly including: a shaft forming the center of rotation of a motor; a rotor part rotatably coupled to the shaft; a first stopper coupled to an upper portion of the rotor part in an axial direction to support the rotor part; a second stopper coupled to a lower portion of the rotor part in the axial direction to support the rotor part; a first bearing part coupled to an upper portion of the first stopper in the axial direction; a second bearing part coupled to a lower portion of the second stopper in the axial direction; a diffuser part supporting the first bearing part and coupled to an upper end of the first stopper; and a motor housing formed integrally with the diffuser part and receiving the first and second bearing parts therein.

The rotor part may include an annular rotor core and a plurality of rotor poles protruded outwardly from the rotor core.

The first stopper may be formed as a balancing member for maintaining rotation balance of a switched reluctance motor.

The switched reluctance motor assembly may further include a stator part including a stator yoke receiving the rotor part therein and stator salient poles formed to be spaced apart from the rotor poles so as to correspond to the rotor poles and formed to be protruded inwardly of the stator yoke.

The switched reluctance motor assembly may further include an impeller part coupled to an upper portion of the diffuser part in the axial direction and rotatably coupled to the shaft.

The diffuser part may include at least one connecting member coupled integrally with the motor housing.

The connecting member may be formed along an outer circumference of the diffuser part and be protruded from an outer circumferential surface of the diffuser part to thereby be coupled integrally with the motor housing.

The switched reluctance motor assembly may further include a sensing magnet formed at a lower portion of the second bearing part in the axial direction and corresponding to the rotor part; and a printed circuit board disposed at a lower portion of the sensing magnet in the axial direction and having a hall sensor attached thereto so as to face the sensing magnet.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of a switched reluctance motor assembly according to a preferred embodiment of the present invention;

FIG. 2 is a partial perspective view of an integral structure of a diffuser part and a motor housing according to the preferred embodiment of the present invention;

FIG. 3 is a cut-away perspective view of the integral structure of the diffuser part and the motor housing shown in FIG. 2; and

FIG. 4 is a schematic cross-sectional view of a rotor part and a stator part according to the preferred embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The objects, features and advantages of the present invention will be more clearly understood from the following detailed description of the preferred embodiments taken in conjunction with the accompanying drawings. Throughout the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant descriptions thereof are omitted. Further, in the following description, the terms “first”, “second”, “one side”, “the other side” and the like are used to differentiate a certain component from other components, but the configuration of such components should not be construed to be limited by the terms. Further, in the description of the present invention, when it is determined that the detailed description of the related art would obscure the gist of the present invention, the description thereof will be omitted.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

FIG. 1 is a cross-sectional view of a switched reluctance motor assembly according to a preferred embodiment of the present invention; FIG. 2 is a partial perspective view of an integral structure of a diffuser part and a motor housing according to the preferred embodiment of the present invention; FIG. 3 is a cut-away perspective view of the integral structure of the diffuser part and the motor housing shown in FIG. 2; and FIG. 4 is a schematic cross-sectional view of a rotor part 20 and a stator part 30 according to the preferred embodiment of the present invention.

The switched reluctance motor assembly according to the preferred embodiment of the present invention may include a shaft 10 forming the center of rotation of a motor, a rotor part 20 rotatably coupled to the shaft 10, a first stopper 41 coupled to an upper portion of the rotor part 20 in an axial direction to support the rotor part 20, a second stopper 42 coupled to a lower portion of the rotor part 20 in the axial direction to support the rotor part 20, a first bearing part 71 coupled to an upper portion of the first stopper 41 in the axial direction, a second bearing part 72 coupled to a lower portion of the second stopper 42 in the axial direction, a diffuser part 60 supporting the first bearing part 71 and coupled to an upper end of the first stopper 41; and a motor housing 80 formed integrally with the diffuser part 60 and receiving the first and second bearing parts 71 and 72 therein.

In the switched reluctance motor assembly according to the preferred embodiment of the present invention, an integral structure of the diffuser part 60 and the motor housing 80 is implemented, such that separate components for the support structures of upper and lower bearing parts are omitted, thereby making it possible to improve precision of concentricity of the upper and lower bearing parts. In addition, distortion of concentric parts of the bearing parts due to an assembling error that may be generated at the time of assembling the bearing parts is prevented, thereby making it possible to improve driving reliability and operation performance of the switched reluctance motor assembly. A detailed description of each component of the switched reluctance motor and the integral structure of the diffuser part 60 and the motor housing 80 will be provided below.

The shaft 10 forms the center of rotation of the motor and is extended in the axial direction. Particularly, the axial direction in the present invention, which is based on a direction in which the shaft 10 is formed, refers to directions toward upper or lower portions based on the shaft 10 shown in FIG. 1. A rotor part 20 to be described below is coupled to the shaft 10 forming the center of rotation of the motor.

The rotor part 20 may be configured to include an annular rotor core 21 and a plurality of rotor poles 22 protruded outwardly from the rotor core 21. The rotor core 21 has a hollow hole formed at a central portion thereof, and the shaft 10 is fixedly coupled to the hollow hole to transfer rotation of the rotor part 20 to the outside. The plurality of rotor poles 22 may be formed to be protruded outwardly along an outer circumferential surface of the rotor core 21 and be formed to correspond to stator salient poles 32 to be described below.

The first stopper 41 is coupled to the upper portion of the rotor part 20 in the axial direction to serve to support the rotor part 20. The first stopper 41 is coupled to the shaft 10 while supporting the rotor part 20, thereby rotating together with the rotor part 20. The first stopper 41 may support the rotor part 20 in the axial direction and be formed as a balancing member made of a resin such as a plastic, or the like, to adjust rotation balance at the time of rotation of the motor. When the first stopper is used as the balancing member, it senses a position at which rotation unbalance is generated and performs a cutting-process, thereby making it possible to balance the rotation of the motor. The balancing member may be formed by processing a plastic, or the like, or be formed integrally with the rotor part 20 through injection-molding.

The second stopper 42 is coupled to the lower portion of the rotor part 20 in the axial direction to serve to support the rotor part 20. The second stopper 42 has a configuration similar to that of the first stopper 41 described above. In addition, a material and a manufacturing method of the second stopper 42 are the same as those of the first stopper 41 described above. The second stopper 42 may also be used as a balancing member made of a plastic material to maintain balance for rotation of the rotor part 20 Although not shown, it is obvious to those skilled in the art to change the design so as to detect a rotation position of the rotor part 20 by forming a sensing groove in a lower end surface of the second stopper 42 in the axial direction and forming a sensor part 70 at a position corresponding to that of the sensing groove formed in the lower end surface of the second stopper 42. However, in the preferred embodiment of the present invention, as shown in FIG. 1, the position of the rotor part 20 may be detected using a sensing magnet 91 and a hall sensor 93 attached on a printed circuit board 92. The hall sensor 93, which is an element having a voltage varied according to strength of a magnetic field, uses a phenomenon (a hall effect) in which when a magnetic field is formed vertically to a direction of a current flowing in a conductor, a potential difference is generated in a direction vertical to that of the current flowing in the conductor. Therefore, the sensing magnet 91 is formed so that N and S poles intersect with each other, and rotates together with the rotor part 20 coupled to the shaft according to the rotation of the rotor part 20 to sense magnetic fields of the N and S poles and sense the position of the rotor part 20, thereby making it possible to detect revolutions per minute (RPM). Since a method of sensing the rotor part 20 using the sensing magnet 91 and the hall sensor 93 is the same as a general sensing method of detecting a magnetic field of a magnet using a hall sensor, a detailed description thereof will be omitted.

The first bearing part 71 is a component rotating the rotor part 20 while supporting weight in the axial direction in the shaft 10 including the rotating rotor part 20 and a load applied to the shaft 10. The first bearing part 71 is coupled to the upper portion of the first stopper 41 in the axial direction and is formed to be received in a motor housing to be described below. Particularly, in the preferred embodiment of the present invention, since the first bearing part 71 may be supported and fixed by an integral structure of a diffuser part 60 and a motor housing 80 to be described below, distortion due to an assembling error generated at the time of assembling the first bearing part 71 is prevented, thereby making it possible to improve precision of assembling concentricity with the second bearing part 72 disposed at a lower portion.

The second bearing part 72 may be coupled to the lower portion of the second stopper 42 in the axial direction. The second bearing part 72 is also coupled so as to be disposed in the motor housing 80 together with the first bearing part 71. Since a description of specific functions and actions of the second bearing part 72 is overlapped with that of the first bearing part 71, it will be omitted. As described above, the first bearing part 71 is supported by the integral structure of the diffuser part 60 and the motor housing 80, thereby making it possible to easily secure the concentricity of the first and second bearing parts 71 and 72.

The diffuser part 60 may be formed integrally with the motor housing 80 enclosing an outer side of the switched reluctance motor assembly. Here, a meaning that the diffuser part 60 is formed integrally with the motor housing 80 is that the diffuser part 60 is formed integrally with the motor housing 80 through a single mold at the time of being manufactured or is coupled to or supported by the motor housing 80 through a separate member. As shown in FIGS. 2 and 3, a separate connecting member 63 may be formed at an outer circumferential surface of the diffuser part 60 so as to be coupled integrally with the motor housing 80. In addition, the connecting member 63, the motor housing 80, and the diffuser part 60 may be formed integrally with each other through a single mold. Since the diffuser part 60 is formed integrally with the motor housing 80, a separate member that has been used in order to fix the diffuser part 60 in the prior art is unnecessary, and the bearing part 71 may be fixed and supported through the integral structure of the diffuser part 60 and the motor housing 80. Therefore, the distortion, or the like, of the first bearing part 71 is prevented, thereby making it possible to more stably perform an operation, or the like, of the first bearing part 71.

Meanwhile, in the diffuser part 60, pressure of air sucked by an impeller part 50 to be described below increases in diffusers 61 of the diffuser part 60, the air of which the pressure increases as described above, is supplied to return channels 62 disposed at a lower side through a space formed between an inner circumferential surface of the motor housing 80 covering an upper portion and an outer circumferential surface of the diffuser part 60, and the air supplied to the return channels 62 as described above is guided to a central portion by the return channels 62 and is blown toward the motor, such that the air is discharged while cooling the motor.

The impeller part 50 is coupled to an upper portion of the diffuser part 60 in the axial direction and is coupled to the shaft 10. The impeller part 50 is coupled to the shaft 10 to rotate together with the shaft 10 at the time of the rotation of the motor, thereby sucking external air. Particularly, an example of a vacuum cleaner module including the switched reluctance motor assembly is shown in FIG. 1. Here, the impeller part 50 rotates in order to introduce the air from the outside at the time of an operation of the cleaner.

As shown in FIG. 4, a stator part 30 is configured to include a stator yoke 31 and stator salient poles 32. The stator yoke 31 may include a hollow hole formed therein so as to receive the rotor part 20 therein, and a plurality of stator salient poles 32 may be formed to be protruded from an inner surface of the stator yoke 31 and correspond to the rotor poles 22 of the rotor part 20. A current is applied to the stator salient poles 32 of the stator yoke 31 to form a magnetic flux path through the stator salient poles 32 and the rotor poles 22 of the rotor part 20 facing the stator salient poles 32, such that the rotor part 20 rotates.

The motor housing 80 is formed at an outer side of the rotor part 20, the stoppers, and the first and second bearing parts 71 and 72 so as to be spaced apart from the rotor part 20, the stoppers, and the first and second bearing parts 71 and 72 and to enclose the rotor part 20, the stoppers, and the first and second bearing parts 71 and 72. The motor housing 80 structurally protects components received therein, such as the rotor part 20, the stator part 30, and the like, and prevents other foreign materials from being introduced from the outside thereinto, thereby making it possible to improve reliability in the operation of the motor.

According to the preferred embodiment of the present invention, the diffuser part of the switched reluctance motor assembly is manufactured and formed integrally with the motor housing, thereby making it possible to improve reliability and productivity in manufacturing the motor.

In addition, the diffuser part of the switched reluctance motor assembly is coupled integrally with the motor housing, thereby making it possible to omit a separate member for fixing the diffuser part and reduce vibration generated according to driving of the motor and noise according to the vibration.

Further, the diffuser part of the switched reluctance motor assembly is coupled integrally with the motor housing, such that a coupling process using a separate screw for assembling the diffuser part and the bearing part to each other is omitted, thereby making it possible to more easily secure the concentricity of the upper and lower bearing parts.

Furthermore, the concentricity of the bearing parts is easily secured, thereby making it possible to reduce vibration and noise of the bearing parts that may be generated according to the driving of the motor.

Moreover, the concentricity of the bearing parts is secured to reduce the generation of the vibration and the noise in the bearing parts, thereby making it possible to secure operation performance and driving reliability of the product according to the driving of the motor.

In addition, the diffuser part and the motor housing of the switched reluctance motor assembly are integrated with each other, thereby making it possible to more stably form a fixing and supporting structure of the bearing part and stably perform an operation of a product to which the switched reluctance motor assembly is used. Therefore, a fault and an operation error of the product are prevented, thereby making it possible to increase a lifespan of the product.

Although the embodiments of the present invention have been disclosed for illustrative purposes, it will be appreciated that the present invention is not limited thereto, and those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention.

Accordingly, any and all modifications, variations or equivalent arrangements should be considered to be within the scope of the invention, and the detailed scope of the invention will be disclosed by the accompanying claims. 

What is claimed is:
 1. A switched reluctance motor assembly comprising: a shaft forming the center of rotation of a motor; a rotor part rotatably coupled to the shaft; a first stopper coupled to an upper portion of the rotor part in an axial direction to support the rotor part; a second stopper coupled to a lower portion of the rotor part in the axial direction to support the rotor part; a first bearing part coupled to an upper portion of the first stopper in the axial direction; a second bearing part coupled to a lower portion of the second stopper in the axial direction; a diffuser part supporting the first bearing part and coupled to an upper end of the first stopper; and a motor housing formed integrally with the diffuser part and receiving the first and second bearing parts therein.
 2. The switched reluctance motor assembly as set forth in claim 1, wherein the rotor part includes an annular rotor core and a plurality of rotor poles protruded outwardly from the rotor core.
 3. The switched reluctance motor assembly as set forth in claim 1, wherein the first stopper is formed as a balancing member for maintaining rotation balance of a switched reluctance motor.
 4. The switched reluctance motor assembly as set forth in claim 1, further comprising a stator part including a stator yoke receiving the rotor part therein and stator salient poles formed to be spaced apart from the rotor poles so as to correspond to the rotor poles and formed to be protruded inwardly of the stator yoke.
 5. The switched reluctance motor assembly as set forth in claim 1, further comprising an impeller part coupled to an upper portion of the diffuser part in the axial direction and rotatably coupled to the shaft.
 6. The switched reluctance motor assembly as set forth in claim 1, wherein the diffuser part includes at least one connecting member coupled integrally with the motor housing.
 7. The switched reluctance motor assembly as set forth in claim 6, wherein the connecting member is formed along an outer circumference of the diffuser part and is protruded from an outer circumferential surface of the diffuser part to thereby be coupled integrally with the motor housing.
 8. The switched reluctance motor assembly as set forth in claim 1, further comprising: a sensing magnet formed at a lower portion of the second bearing part in the axial direction and corresponding to the rotor part; and a printed circuit board disposed at a lower portion of the sensing magnet in the axial direction and having a hall sensor attached thereto so as to face the sensing magnet. 